Hi r-help-boun...@r-project.org napsal dne 19.01.2011 00:03:10:
> > On Jan 18, 2011, at 5:25 PM, kurt_h...@nps.gov wrote: > > > Greetings > > I have a bunch of NAs in a column of categorical variables > > designating > > the size classes (e.g., smallest to largest: 1,2,3,4) of cave > > crickets. > > I'd like to substitute "U" (for unknown) for the NAs. Can anyone > > give me > > an idea how to do this? Thanks in advance. > > > vect=factor(c(1,2,3,4,NA)) > > vect > [1] 1 2 3 4 <NA> > Levels: 1 2 3 4 > > levels(vect) <- c(levels(vect), "U") > > vect[is.na(vect)] <- "U" > > > > vect > [1] 1 2 3 4 U > Levels: 1 2 3 4 U You can set also NA as an additional level through exclude=NULL option factor(vect, exclude=NULL) [1] 1 2 3 4 <NA> Levels: 1 2 3 4 <NA> Regards Petr > > > > -- > David. > > > Cheers > > Kurt > > > > *************************************************************** > > Kurt Lewis Helf, Ph.D. > > Ecologist > > EEO Counselor > > National Park Service > > Cumberland Piedmont Network > > P.O. Box 8 > > Mammoth Cave, KY 42259 > > Ph: 270-758-2163 > > Lab: 270-758-2151 > > Fax: 270-758-2609 > > **************************************************************** > > Science, in constantly seeking real explanations, reveals the true > > majesty > > of our world in all its complexity. > > -Richard Dawkins > > > > The scientific tradition is distinguished from the pre-scientific > > tradition > > in having two layers. Like the latter it passes on its theories but > > it > > also passes on a critical attitude towards them. The theories are > > passed > > on not as dogmas but rather with the challenge to discuss them and > > improve > > upon them. > > -Karl Popper > > > > ...consider yourself a guest in the home of other creatures as > > significant > > as yourself. > > -Wayside at Wilderness Threshold in McKittrick Canyon, Guadalupe > > Mountains > > National Park, TX > > > > Cumberland Piedmont Network (CUPN) Homepage: > > http://tiny.cc/e7cdx > > > > CUPN Forest Pest Monitoring Website: > > http://bit.ly/9rhUZQ > > > > CUPN Cave Cricket Monitoring Website: > > http://tiny.cc/ntcql > > > > CUPN Cave Aquatic Biota Monitoring Website: > > http://tiny.cc/n2z1o > > > > ______________________________________________ > > R-help@r-project.org mailing list > > https://stat.ethz.ch/mailman/listinfo/r-help > > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > > and provide commented, minimal, self-contained, reproducible code. > > David Winsemius, MD > West Hartford, CT > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
